"We need a Senator who will fight with President Trump to defend the Constitution, build the wall, stand up for the unborn, push for lower taxes, make health care more affordable, and protect the Second Amendment," Byrne said in the statement.

Jones was elected to the Senate in a special election in December 2017, defeating Republican Roy Moore. Jones's victory followed news reports that Moore had pursued relationships with teenagers when he was in his 30s.

Jones is up for reelection in 2020, when Alabama voters will decide whether to keep him in office for a full six-year term.

Byrne, in an interview with The Hill last June, called Jones a "great guy" and a "terrific lawyer," but added that he believed Alabama needed a senator who would vote differently.

“We need somebody who’s going to go win that election and then get in that position over there and represent Alabama," he said at the time.